Evaluation of Heavy Metals and Pesticides Contents in Market-Gardening Products Sold in Some Principal Markets of Ouagadougou (Burkina Faso)

Abstract

Pesticides and heavy metals are persistent organic pollutants responsible for immune deficiency, certain types of cancer, and decreased length of pregnancy.In this study, 20 chemical pesticides and 4 heavy metals were detected from 120 samples of 4 types of vegetables and 40 samples of babenda collected from Ouagadougou principal markets. The "babenda" is a Burkinabe dish made mainly of leafy vegetables (Hibiscus sabdariffa, Amaranthus hybridus, and Cleome gynandra) coarsely chopped and millet or rice that was boiled together.A multi-residue method was developed to detect the pesticides in the samples collected by gas chromatography, with micro electron capture detector. The concentration of cadmium, lead, mercury and arsenic were obtained from the 120 vegetables samples by using an atomic absorption spectrometer. Residues of pesticides were detected in 87% of the samples, and among the positive samples, 58.40% contained concentrations higher than the limit of maximum residue (LMR). Thirteen active pesticide residues were detected in the vegetables. The contents of the majority of pesticides residues were higher than the LMR. Seven active ingredients were detected in the babenda. 50% of the samples had more than one pesticide residue. The heavy metal concentrations ranged from 0.0098 to 2.66 mg.kg -1 for Hg; 0.01 to 1.146 mg.kg -1 for Pb; 0.016 to 1.72 mg.kg -1 for Cd and 0.012 to 1.885 mg.kg -1 for As. The relative abundance of heavy metals in the vegetables followed the sequence Cd (0.018 mg.kg -1) > Pb (0.016 mg.kg -1) > As (0.012 mg.kg -1) > Hg (0.0098 mg.kg -1). In addition, the concentration of heavy metals in the samples collected from the different markets exceeded the threshold according to the lawful maximum concentration (CMR) established in France. The continuous follow-up and a strict regulation of these pollutants in the vegetables particularly, are necessary.

Assessment of onions contamination by pesticides residues and characterization of market gardeners’ cultural practices in the region of Boucle du Mouhoun (Burkina Faso)

“…This situation results from the inappropriate or abusive use of pesticides and from the lack of environmental education for farmers (Licciardi et al, 2007). However, our results are in contrast to those of Son et al (2017) and Tarnagda et al (2019) who reported respectively that pyrethroid and organochlorines are the predominant families. Those differences could be explained by the diversity of pesticides used depending on the crop areas.…”

Comparative Assessment of the Quality of Parkia Biglobosa Trunk Bark Powders Jacq. Benth (Fabaceae-Mimosoideae) Intended for the Pharmaceutical Production of Phyto-Drugs

“…This may be due to the misuse of pesticides and the lack of environmental education of farmers; these powders cannot be directly used. Any use of raw material with pesticide contents above the limit requires prior treatment (bark washing, powder decoction), as heat and washing reduce the concentration of pesticides [24].…”

Concentrations Of Heavy Metals In Leafy Vegetables Taken From A Local Market In Kundra, Koraput, Odisha, India

“…Zinc is required to develop even functions and express genes in our bodies in addition to helping in the synthesis of different proteins and healing of wounds. [15][16][17] Our study suggests the zinc concentration in Methi leaves is the highest while it is the lowest in Drumstick leaves, so the leaves are listed in the following order: Methi leaves > Lal Bhaji > Drumstick leaves. The zinc is present in this kind of leaves is extremely low.…”